Latch and lock for doors



sept. 15, 1925.

. C. HOFFMAN LATCH AND LOCK FOR DORS Filed 00t- 9. 1922 s AsheetS-slwet 1 wud",

Sept. l5, 1925. 1,553,532 Y c. HoFFMAN LATCH AND LOCK FOR DOORS Filedoct. 9, 1922 I 3 sheets-sheet 2 @zur j C. ,HOFFMAN LATCH AND LOCK FOR DOORS v Sept. l5, 1925'.

Filed 0Gt-. 9. 1922 3 Sheets-Sheet 3 Patented Sept. l5, 1925.

UNITED STATES CARL HOFFMAN, F ALLENTOWN, PENNSYLVANIA.

LATCH AND LOCK FOR DOOR/S.

Application filed October 9, 1922. Serial XNo. 593,285.

.To all whom t may concern:

Be it known that I, CARL HOFFMAN, a

i citizen of the United States, residing at Allentown, in the county of Lehigh and State of Pennsylvania, have invented certain new and useful Improvements in Latches and Locks for Doors; and I do hereby declare the following to be a full, clear, and exact description of theinvention, such as will enable others skilled Vin the art to which it appertains to make and use the same.

My invention relates to locks, and the obj ect of the invention is to provide a simple latch and lock mechanism, with improved means for eiecting the latching and locking operations of the parts, and one whereinthe arrangement of the elements affords a maximum of security both as a latch and a lock.

In the drawings, Figure l is a view in side elevation showing the parts in latching position, the cover plate of the lock case being removed and portions of the door audits casing being shown in section. Figure 2 is a similar view but with the lock protracted. Figure 3 is a cross sectional view on line 3 3, Figure l. Figure 4 is a vertical sectional view on line 4 4, Figure l. Figure 5 is a sectional view on line 5 5 of Figure 4. Figure 6 is an elevation showing the dead bolt protracted. Figure 7 is a cross sectional view on line 7 7, Figure l. Figure 8 is a perspective view of the lock case with the cover plate removed, and Figures 9 and lO are similar views of the latch and the bolt, respectively.

The elenfents of my improved lock are assembled in the usual lock case l composed of edge plate, bed plate and cover, each provided with the necessary openings and spacing posts. The latch is shown at 2 and is formed integrally with a skeleton plate 3, an enlargment 4 at the other end of the plate serving as the means against which wings 5 of a knob operated spindle 6 bear in moving the plate with its latch against the tension of spring 7. The enlargement 4 is grooved as at 8 to Work over the guide 9 of the lock case. Depending from the lower side of the skeleton frame is a lip 10 adapted Jfor cooperation with a stop pin 12V to prevent movement of the latch.

At 2() I have shown a tumbler controlled lock adapted for manipulation by a key engaging talons 2l and 22, two turns oi" the key being necessary to set the lock in fully protracted position,Y the first turn merely moving it to the position indicated by dotted line A, Figure 2. The bolt has a slot 23 which serves to'guide it over a lug 24 of the lock case, and it is also provided with a stud 25 which engages one or the other of three cut outs 26 of the tumbler 27 by which it is held in its various positions. A spring 28 insures engagement of the cut out portions of the tumbler with a stud 25 of the lock. The tumbler is pivoted on the post 29, and has avsemi-circular recess 30 which is designed to receive the stop pin l2 when the parts are in the position shown in Fig-l ure l. Movement of the tumbler forengagement with stud 25 is effected by a key turning against the lower curved edge of the tumbler. The lock bolt 20 has a lever pivotally mounted thereon and which serves to hold the latch in protracted position when the lock bolt is extendedits full distance. The long arm 40 of this lever at its upper end is fitted between two laterally projecting pins 4l of the latch and in the position of the part-s shown in Figure l in` no way interferes with manipulation of the latch. As shown in Figure 2, however, when the l'ock bolt is protracted to its full extent it carries the lever to a point where its lower short arm-42 bears against the edge plate of the lock case so that turning of the latch 2 will be impossible, pressure to move the latch inwardly being met with the resistance against the lever of the edge plate. It will be seen that in order to dislodge the parts from this position key manipulation is necessary, the key first mo-ving the tumbler and then the lock bolt to its half-way position and on further turning to its fully retracted position. The latch is then free to move through actuation of the winged spindle 6. It is manifest that it desired the stop pin 12 may be pushed into the path of the latchy lip l0 and the tumbler 27 to prevent actuation of the latch and movement of the tumbler. As a further means for preventing operation of the parts I provide a dead bolt 50 suitably guided in its sliding movements by a lug 5l of the lock case and a spring 52 on the cover plate which bears down against and holds the bolt in position. This bolt has an upstanding arm 53 which when the bolt is shot partly closes the key opening, thus preventing insertion of a key. The bolt is operated by a permanently fixed key 54.

In the assembling of the parts I lind that most satisfactory results are obtained by :forming the wings 5 with a hub having a squared bore to receive the squared portion v'of the spindle 6, the inner knob being trol of a person within doors.

I claim as my invention:

l. A latch and lock mechanism including a lock case, a spindle operated spring controlled latch, a tumbler controlled lock bolt, a tumbler for the latter, a common means 'for independently engaging and locking` both latch and tumbler, and a lever pivoted on said lock bolt and engaging said latch whereby the latter will be held against movement when said lock bolt is protracted.

2. A latch and lock mechanism including a lock case, a spindle operated spring controlled latch, a tumbler controlled lock bolt, a tumbler for the latter, a common means for independently engaging and locking both latch and tumbler, and a two arm lever piv.

oted on said lock bolt and having one arm trolled lock bolt, a lever pivoted on said lock bolt and engaging said latch whereby the latter will be held against movement when said lock bolt is protracted, and a transversely movable pin engageable with said latch and the tumbler of said lock bolt for preventing operation of said key controlled,

lock bolt to withdraw said lever.

4; A latch and lock mechanism including a lock case, a spindle operated spring controlled latch, said latchV having a depending portion, a key controlled lock bolt, a spring vactuated tumbler vcooperating with said lock bolt to hold it in various positions, means carried by said lock bolt and engaging said latch whereby the latter will be held against movement when said lock bolt is protracted, and a stop pin adapted to lbe projected into the path of said depending portion of said latch and said springactuated tumbler to prevent operation of said latch 4and movement ot said lock bolt to withdraw said holding means.

In testimony vwhereof I have signed this specification. Y

CARL HOFFMAN. 

